What is Knee Osteoarthritis?

Osteoarthritis, more generally referred to as wear-and-tear arthritis, is a disease in which the natural cushion between joints deteriorates. When this occurs, the joints rub more tightly against one another, resulting in a loss of cartilage's shock-absorbing properties. The rubbing causes pain, oedema, stiffness, and a diminished capacity to move, as well as the production of bone spurs in certain cases. When this happens in the knee joint specifically, it is called knee osteoarthritis.

Other types of knee arthritis (Osteoarthritis vs. rheumatoid arthritis)

There are many types of arthritis.

Osteoarthritis and rheumatoid arthritis are the two most frequent kinds of knee arthritis.

The most prevalent kind is Osteoarthritis. It is a degenerative disease that results from the slow deterioration of the cartilage in the knee joint. It often manifests itself after midlife.

Knee Arthritis can also occur as a result of a knee injury. A torn knee meniscus, ligament damage, or knee fracture can all result in post-traumatic arthritis. Symptoms may not manifest for several years.

Rheumatoid arthritis is a chronic inflammatory disease that can strike anyone at any age. It affects the entire body and may involve additional joints and symptoms such as knee infiltration causing knee synovitis. It is a type of autoimmune disease.

What causes knee osteoarthritis?

Osteoarthritis is a degenerative condition that affects the articular cartilage (mostly type II) that cushions the articular surfaces of bones.

Articular cartilage is generally maintained in a state of chemical equilibrium; however, as OA develops, the chemical interactions are interrupted, resulting in alterations to the cartilage's collagen:

Disruption of the balance, resulting in an unorganized pattern of collagen and a decrease in the suppleness of the articular cartilage.

This results in cartilage cracking and fissuring, eroding the articular surface.

The cartilage that has been injured is irreversible.

The cartilage will continue to deteriorate.

Once the cartilage has deteriorated, the bone surfaces begin to be damaged.

The bone will continue to spurs (osteophytes).

Ligament laxity and muscular atrophy are frequently observed as the illness advances.

Factors that lead to these changes are:

Age; As a person ages, cartilage's capacity to regenerate reduces.

Genetics; This includes genetic variations that may increase a person's risk of developing knee osteoarthritis. Additionally, it might be caused by hereditary anomalies in the form of the bones around the knee joint.

Weight; Weight puts additional pressure on all joints, but particularly the knees. Each pound gained adds 3 to 4 pounds of additional weight to your knees.

Gender; Women over the age of 55 are more likely than males to have knee osteoarthritis.

Sporting events; Athletes who participate in tennis, soccer, or long-distance running may be at an increased risk of getting knee osteoarthritis. This implies that players must use caution to avoid injury. It is critical to remember, however, that moderate activity strengthens joints and may help reduce the incidence of osteoarthritis. Indeed, weak muscles around the knee can contribute to the development of osteoarthritis.

Injuries caused by repetitive stress; are frequently the effect of a person's line of work. Individuals who have professions that require frequent joint stress, such as squatting, kneeling, or lifting large weights (55 pounds or more), are more prone to develop knee osteoarthritis due to the persistent pressure on the joint.

What Are the Symptoms of Knee Osteoarthritis

Symptoms of knee Osteoarthritis are:

  • Knee Pain associated with movement
  • Stiffness, particularly in the early morning
  • Range of motion loss
  • Aches and pains associated with extended sitting or laying
  • Palpation of the joint line produces knee pain.
  • Enlargement of the joints

How Is Arthritis of the Knee Diagnosed?

Your doctor will begin the diagnosis of knee osteoarthritis with a physical examination. Additionally, your doctor will review your medical history and make notes of any symptoms. Make a note of what makes the pain worse or better to assist your doctor in determining if the cause of your pain is osteoarthritis or something else. Additionally, determine whether anyone else in your family suffers from arthritis. Your physician may prescribe further testing, which may include the following:

Magnetic resonance imaging (MRI) scans, which can reveal bone and cartilage damage as well as the existence of bone spurs


Xrays can show the following findings:

  • narrowing of joint space
  • Formation of osteophytes
  • Sclerosis of the subchondral bone
  • Cysts in the subchondral region
  • In the early stages, there is just a little narrowing of the joint space.
  • In severe OA, the joint line may vanish entirely.

When X-rays do not reveal a clear cause of joint ache or when the X-rays imply that other types of joint tissue may be injured, MRI scans may be requested. Blood tests may be conducted to rule out other possible causes of pain, such as rheumatoid arthritis, a separate kind of arthritis caused by an immune system disease.

How Is Osteoarthritis of the Knee Treated

The treatment for knee osteoarthritis can be divided into conservative, medical, and surgical management.

Treatment always starts with conservative measures and progresses to surgery once conservative measures have been explored. There are several conservative therapy options available for knee OA. These therapies have no effect on the underlying illness process; rather, they aim to alleviate discomfort and maximize functioning for as long as feasible.

Conservative Treatment Options

Exercise therapy within physiotherapy is the primary conservative treatment for knee osteoarthritis. Physiotherapy is often comprised of the following:

  • Education of the patient
  • Physiotherapy via exercise
  • Modification of activity
  • Weight loss advice
  • Bracing for the knee support

Patient education and physiotherapy are the first-line treatments for all individuals with symptomatic knee osteoarthritis. The highest outcomes have been seen when supervised activities are combined with a home fitness regimen. If the workouts are discontinued after six months, these advantages are lost.

Weight reduction is beneficial at every stage of knee OA. It is appropriate in people who have symptomatic OA and a BMI of more than 25. The greatest prescription for weight loss is to maintain a healthy diet and engage in low-impact aerobic activity.

In OA, knee bracing may be employed. Knee Braces of the offloading kind that distribute the weight away from the affected knee compartment. This can be beneficial when a valgus or varus deformity exists.

Medical Treatment:

Other non-physiotherapy based interventions include pharmacological management:

  • Acetaminophen
  • Nonsteroidal anti-inflammatory drugs (NSAIDs)
  • COX-2 inhibitors
  • Glucosamine and chondroitin sulfate
  • Corticosteroid injections
  • Hyaluronic acid (HA)

For individuals with symptomatic OA, drug therapy in conjunction with Physio should be the initial line of treatment. While there are several NSAIDs available, care should be exercised while prescribing NSAIDs owing to their potential negative effects.

Supplements containing chondroitin sulfate and glucosamine are available. They are structural elements of articular cartilage, and it is believed that a supplement will benefit its health. There is no compelling evidence that these substances are effective for knee OA.

Intra-articular corticosteroid injections may be beneficial in the treatment of symptomatic knee osteoarthritis.

Another injectable alternative is intra-articular hyaluronic acid injections (ex: Cingal, Synvisc One, Synolis). With the local distribution of hyaluronic acid injection knee joint functions well as HA acts as a lubricant and may assist in increasing the joint's natural HA production.

 Cigal  Synvisc One  Synolis

Surgical interventions:

If your pain and lack of mobility significantly impair your quality of life, your doctor may prescribe surgery.

Partial surgery to remove damaged tissue is an option for OA, or the total knee replacement, which results in an artificial knee joint.

This category comprises arthroscopy, osteotomy, and arthroplasty operations.


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